Presentation on theme: "The magical world of BIOENERGY Social and political implications as well as some science Emily J. May Energy Alternatives February 28, 2007."— Presentation transcript:
The magical world of BIOENERGY Social and political implications as well as some science Emily J. May Energy Alternatives February 28, 2007
What is Bioenergy? Bioenergy is: “energy derived from recently living material such as wood, crops, or animal waste.” (versus decayed materials that comprise fossil fuels) Can be burned directly for heat or converted to biofuels such as biodiesel or ethanol. Currently approx 1 million Mtoe, projected to double in 25 years 1% of cumulative investment
Come On Baby Light My Fire: A Brief History of Biofuels Humans have derived energy from organic matter for millennia. wood and animal dung Grass fuel for animals as agriculture and domestication began. Animal fat candles- Industrial Revolution
Traditional Biomass Burning of wood, animal dung and plant matter Common in developing countries as a primary energy source Provides 48 EJ to world primary energy (approximate figure)
The Path to Prosperity? “ Haiti might be able to supply the Dominican Republic with biofuels while strengthening its own economy and mitigating the increased greenhouse gases that can accompany economic development. [Haiti] has a large agrarian citizenship, a eastern neighbor eager for biofuels, and a consistent mandate from the international community to increase standard-of-living. Haiti…may be able to strengthen its ravaged economy by helping a neighbor decrease its use of fossil fuels - which can only be good for an island poised to suffer from the adverse effects of climate change.” http://www.haitiinnovation.org/node/308?gclid=CI6TqJq0zYoC FSZfQAodyW-UdA
“New” Biomass Produced on a large commercial scale in industrialized nations- 7% primary energy Provides 9 EJ (2%) of world primary energy Energy Crops: Plants that are grown specifically for use as biofuels Organic Wastes: byproduct of direct uses of biomass, eg. agriculture.
Energy Crops Woody crops: trees harvested for biofuel Europe, U.S. and Australia Agricultural crops most common are sugar cane and maize for conversion into liquid fuels Plants such as sunflowers and soybeans are grown for the oil in their seeds’ conversion to biodiesel
ETHANOL U.S. 101 plants- 4.8 billion gallons/year 2005- 4 billion gallons used = 1.2 fewer cars (?) Brazil PRO-ALCOOL is the world’s biggest biomass system. Vehicles run on “gasohol” (26% ethanol) Developed during economic hardship, saved over $40 billion
Organic Wastes Wood Residues: byproduct of plantation thinning Temperate Crop Wastes: unused portion of wheat, maize and corn crops; over a billion tonnes/year. 15-20 EJ Tropical Crop Wastes: sugar and rice, 18 EJ. Animal Wastes: anaerobic digestion of manure can be converted to fuel
Organic Waste Cont. Municipal Solid Waste Landfill Gas anaerobic digestion of biological material produces landfill gas which has been used since the 1970s. Has low efficiency. Commercial and Industrial waste
How Does It All Work? Solid biomass Combustion produces heat energy and CO2. Gaseous fuels Anaerobic digestion: disgester enables bacteria to break down matter, creating heat. Gasifier: hot steam and oxygen + volatiles and char= producer gas
How Does It All Work? Cont. Liquid Fuels Pyrolysis: heating bio material to extract volatile components, then condensed, made into bio-oil. Approx. half the energy of crude oil Synthesis: gasification produces syngas (CO and H2), condensed into liquid. Fermentation: sugars converted to alcohol by organisms such as yeast.
Bioenergy in the US Cheap petroleum has consistently destroyed US bioenergy market second to Windpower in renewables 3% of US energy consumption ethanol and biodiesel currently in use Future: biomass to produce plastics and chemicals
US Biofuel Prices Biodiesel:.50/litre Ethanol maize:.23/litre wood:.62/litre Crude oil, Feb 2007:.60/litre
Focus of the US DOE Biomass Program: An Impressively Convoluted Diagram (no questions please)
Bioenergy in Burlington The McNeil Biomass Plant conventional wood-burning plant that has been in operation since 1984 Uses biogasification: converts organic fuels into “clean” gas McNeil uses 200 tons of locally produced wood per day!
But is it sustainable? 70% from low quality trees and forest residue 25% is byproduct of local sawmills 5% recycled urban wood waste
Burlington’s McNeil Biomass Plant catalytic system cleans gas, compress gas, sends through turbine Emissions are 1/100 of the permitted federal level 50 MW capacity: 1/10 size of Vermont Yankee but still enough power for all of Burlington
Bioenergy in Belize 2002 Johannesburg World Summit Central American Commission on Environment and Development Feasibility of bioenergy in Belize by NGOs GBEP (2006): bioenergy to developing nations Belize has no Clean Development Mechanism (Kyoto Protocol) No large-scale bioenergy production
Freedom from Fossil Fuels! Biofuels “should generate no more heat and create no more carbon dioxide than would have been formed in any case by natural processes.” (106)
BUT WAIT! What about those conversion efficiencies? The low conversion efficiency of biomass to bioenergy is almost as hard to justify as a war for oil “air-dry mass of plant matter produced annually on an area of one hectare can be as little as one tonne.” (112) This produces only 15 GJ/hectare/year!
Burning Bush “Twenty by Ten” introduced in the 2007 State of the Union address proposes a decrease of fossil fuel use in 10 years by replacing 15% with biofuels and increased fuel efficiency of cars by 5% Biofuel production must increase fivefold Seeks $3.6 billion for the research and development of new fuels using "everything from wood chips, to grasses, to agricultural wastes"
“Addicted to Biofuels”? When demand for biofuels exceeds a sustainable production rate, bioenergy is no longer a viable energy source. high level of energy and resource input "All the fossil fuels that are used in the production of corn, in the fertilizers and in the fuel, in the ploughs and transportation and so on and in the distillation process, it becomes almost a very dirty fuel.” –Kurt Davies, Greenpeace USA
Sources cited Bioenergy: US Department of Energy. http://www.energy.gov/energysources/bioenergy.htmhttp://www.energy.gov/energysources/bioenergy.htm “Q&A: Bush’s Energy Reforms” 24 Jan, 2007. http://news.bbc.co.uk/2/hi/americas/6293805.stmhttp://news.bbc.co.uk/2/hi/americas/6293805.stm “US Ethanol Production.” http://www.ksgrains.com/ethanol/useth.htmlhttp://www.ksgrains.com/ethanol/useth.html Boyle, Godfrey. Renewable Energy: Power For a Sustainable Future. Oxford Press 2004, Glasgow. Lallement, Dominque. “The Role and Significance of Latin America in Global Energy Markets.” Amsterdam, 19 Dec. 2006. Nurmi, Dr. Marrku. Central American Carbon Finance Guide. September 2004. http://www.greenstream.net/content/Projects/carbono_en.pdf?from=204215008731975 Riley, Kate M. 27 Feb, 2007. Valenti, Michael. “Preaching to the converted.” Mechanical Engineering, 2001. http://www.memagazine.org/backissues/membersonly/dec01/features/preaching/preaching.html http://www.memagazine.org/backissues/membersonly/dec01/features/preaching/preaching.html